Penrose, Francis: An investigation of the principles of Athenian architecture: or the results of a recent survey conducted chiefly with reference to the optical refinements exhibited in the construction of the ancient buildings at Athens (London [u.a.], 1888)

DISCOVERY OF CURVATURE OF HORIZONTAL LINES OF THE PARTHENON 35

that the courses should recover their parallelism to the external entablature, otherwise the lines of
the coffers of the ceiling would have been at fault.

Plate XIII. also contains measurements of the " scamilli impares " from some of the lower drums
of the columns of the Pronaos and Posticum; and the projection on the upper step of the stylobate
(by plumbing) of the abaci of the four angle columns.

Adjecere bouce paulo plus artis Atlieucz
Scilicet nt fiossem curvo dignoscere rectum.

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